It is important to verify the integrity and authenticity of your ISO image.

The integrity check confirms that your ISO image was properly downloaded and that your local file is an exact copy of the file present on the download servers. An error during the download could result in a corrupted file and trigger random issues during the installation.

The authenticity check confirms that the ISO image you downloaded was signed by Linux Mint, and thus that it isn’t a modified or malicious copy made by somebody else.